AK: Rename RetainPtr => RefPtr and Retained => NonnullRefPtr.

67 files changed, 234 insertions, 234 deletions

diff --git a/Kernel/Devices/DiskPartition.cpp b/Kernel/Devices/DiskPartition.cpp
index 34ebf00ea5..7fc60c733d 100644
--- a/Kernel/Devices/DiskPartition.cpp
+++ b/Kernel/Devices/DiskPartition.cpp
@@ -2,12 +2,12 @@
 
 // #define OFFD_DEBUG
 
-Retained<DiskPartition> DiskPartition::create(Retained<DiskDevice>&& device, unsigned block_offset)
+NonnullRefPtr<DiskPartition> DiskPartition::create(NonnullRefPtr<DiskDevice>&& device, unsigned block_offset)
 {
     return adopt(*new DiskPartition(move(device), block_offset));
 }
 
-DiskPartition::DiskPartition(Retained<DiskDevice>&& device, unsigned block_offset)
+DiskPartition::DiskPartition(NonnullRefPtr<DiskDevice>&& device, unsigned block_offset)
     : m_device(move(device))
     , m_block_offset(block_offset)
 {
diff --git a/Kernel/Devices/DiskPartition.h b/Kernel/Devices/DiskPartition.h
index c4e1b39ee9..7db12eefc2 100644
--- a/Kernel/Devices/DiskPartition.h
+++ b/Kernel/Devices/DiskPartition.h
@@ -5,7 +5,7 @@
 
 class DiskPartition final : public DiskDevice {
 public:
-    static Retained<DiskPartition> create(Retained<DiskDevice>&& device, unsigned block_offset);
+    static NonnullRefPtr<DiskPartition> create(NonnullRefPtr<DiskDevice>&& device, unsigned block_offset);
     virtual ~DiskPartition();
 
     virtual unsigned block_size() const override;
@@ -17,8 +17,8 @@ public:
 private:
     virtual const char* class_name() const override;
 
-    DiskPartition(Retained<DiskDevice>&&, unsigned);
+    DiskPartition(NonnullRefPtr<DiskDevice>&&, unsigned);
 
-    Retained<DiskDevice> m_device;
+    NonnullRefPtr<DiskDevice> m_device;
     unsigned m_block_offset;
 };
diff --git a/Kernel/Devices/FileBackedDiskDevice.cpp b/Kernel/Devices/FileBackedDiskDevice.cpp
index b56aaff6d6..8b05e6e697 100644
--- a/Kernel/Devices/FileBackedDiskDevice.cpp
+++ b/Kernel/Devices/FileBackedDiskDevice.cpp
@@ -7,7 +7,7 @@
 //#define FBBD_DEBUG
 #define IGNORE_FILE_LENGTH // Useful for e.g /dev/hda2
 
-RetainPtr<FileBackedDiskDevice> FileBackedDiskDevice::create(String&& image_path, unsigned block_size)
+RefPtr<FileBackedDiskDevice> FileBackedDiskDevice::create(String&& image_path, unsigned block_size)
 {
     return adopt(*new FileBackedDiskDevice(move(image_path), block_size));
 }
diff --git a/Kernel/Devices/FileBackedDiskDevice.h b/Kernel/Devices/FileBackedDiskDevice.h
index 667f3af427..580f3b531d 100644
--- a/Kernel/Devices/FileBackedDiskDevice.h
+++ b/Kernel/Devices/FileBackedDiskDevice.h
@@ -8,7 +8,7 @@
 
 class FileBackedDiskDevice final : public DiskDevice {
 public:
-    static RetainPtr<FileBackedDiskDevice> create(String&& image_path, unsigned block_size);
+    static RefPtr<FileBackedDiskDevice> create(String&& image_path, unsigned block_size);
     virtual ~FileBackedDiskDevice() override;
 
     bool is_valid() const { return m_file; }
diff --git a/Kernel/Devices/IDEDiskDevice.cpp b/Kernel/Devices/IDEDiskDevice.cpp
index 4c50915e61..5778805981 100644
--- a/Kernel/Devices/IDEDiskDevice.cpp
+++ b/Kernel/Devices/IDEDiskDevice.cpp
@@ -78,7 +78,7 @@
 #define ATA_REG_ALTSTATUS 0x0C
 #define ATA_REG_DEVADDRESS 0x0D
 
-Retained<IDEDiskDevice> IDEDiskDevice::create()
+NonnullRefPtr<IDEDiskDevice> IDEDiskDevice::create()
 {
     return adopt(*new IDEDiskDevice);
 }
diff --git a/Kernel/Devices/IDEDiskDevice.h b/Kernel/Devices/IDEDiskDevice.h
index 7f5cfbd99e..da5f491516 100644
--- a/Kernel/Devices/IDEDiskDevice.h
+++ b/Kernel/Devices/IDEDiskDevice.h
@@ -18,7 +18,7 @@ class IDEDiskDevice final : public IRQHandler
     , public DiskDevice {
     AK_MAKE_ETERNAL
 public:
-    static Retained<IDEDiskDevice> create();
+    static NonnullRefPtr<IDEDiskDevice> create();
     virtual ~IDEDiskDevice() override;
 
     // ^DiskDevice
@@ -55,7 +55,7 @@ private:
 
     PCI::Address m_pci_address;
     PhysicalRegionDescriptor m_prdt;
-    RetainPtr<PhysicalPage> m_dma_buffer_page;
+    RefPtr<PhysicalPage> m_dma_buffer_page;
     word m_bus_master_base { 0 };
     Lockable<bool> m_dma_enabled;
 };
diff --git a/Kernel/Devices/MBRPartitionTable.cpp b/Kernel/Devices/MBRPartitionTable.cpp
index b194855b3e..2d4f733c93 100644
--- a/Kernel/Devices/MBRPartitionTable.cpp
+++ b/Kernel/Devices/MBRPartitionTable.cpp
@@ -3,7 +3,7 @@
 
 #define MBR_DEBUG
 
-MBRPartitionTable::MBRPartitionTable(Retained<DiskDevice>&& device)
+MBRPartitionTable::MBRPartitionTable(NonnullRefPtr<DiskDevice>&& device)
     : m_device(move(device))
 {
 }
@@ -37,7 +37,7 @@ bool MBRPartitionTable::initialize()
     return true;
 }
 
-RetainPtr<DiskPartition> MBRPartitionTable::partition(unsigned index)
+RefPtr<DiskPartition> MBRPartitionTable::partition(unsigned index)
 {
     ASSERT(index >= 1 && index <= 4);
 
diff --git a/Kernel/Devices/MBRPartitionTable.h b/Kernel/Devices/MBRPartitionTable.h
index a3ad937b2c..d5ca9b138f 100644
--- a/Kernel/Devices/MBRPartitionTable.h
+++ b/Kernel/Devices/MBRPartitionTable.h
@@ -31,14 +31,14 @@ class MBRPartitionTable {
     AK_MAKE_ETERNAL
 
 public:
-    MBRPartitionTable(Retained<DiskDevice>&& device);
+    MBRPartitionTable(NonnullRefPtr<DiskDevice>&& device);
     ~MBRPartitionTable();
 
     bool initialize();
-    RetainPtr<DiskPartition> partition(unsigned index);
+    RefPtr<DiskPartition> partition(unsigned index);
 
 private:
-    Retained<DiskDevice> m_device;
+    NonnullRefPtr<DiskDevice> m_device;
 
     ByteBuffer read_header() const;
     const MBRPartitionHeader& header() const;
diff --git a/Kernel/File.cpp b/Kernel/File.cpp
index b366c523b1..693b21ee74 100644
--- a/Kernel/File.cpp
+++ b/Kernel/File.cpp
@@ -9,7 +9,7 @@ File::~File()
 {
 }
 
-KResultOr<Retained<FileDescription>> File::open(int options)
+KResultOr<NonnullRefPtr<FileDescription>> File::open(int options)
 {
     UNUSED_PARAM(options);
     return FileDescription::create(this);
diff --git a/Kernel/File.h b/Kernel/File.h
index ec81adbdf4..cc42cb2a44 100644
--- a/Kernel/File.h
+++ b/Kernel/File.h
@@ -43,7 +43,7 @@ class File : public RefCounted<File> {
 public:
     virtual ~File();
 
-    virtual KResultOr<Retained<FileDescription>> open(int options);
+    virtual KResultOr<NonnullRefPtr<FileDescription>> open(int options);
     virtual void close();
 
     virtual bool can_read(FileDescription&) const = 0;
diff --git a/Kernel/FileSystem/Custody.cpp b/Kernel/FileSystem/Custody.cpp
index 769d4c0de8..6e64359bfa 100644
--- a/Kernel/FileSystem/Custody.cpp
+++ b/Kernel/FileSystem/Custody.cpp
@@ -26,9 +26,9 @@ Custody* Custody::get_if_cached(Custody* parent, const String& name)
     return nullptr;
 }
 
-Retained<Custody> Custody::get_or_create(Custody* parent, const String& name, Inode& inode)
+NonnullRefPtr<Custody> Custody::get_or_create(Custody* parent, const String& name, Inode& inode)
 {
-    if (RetainPtr<Custody> cached_custody = get_if_cached(parent, name)) {
+    if (RefPtr<Custody> cached_custody = get_if_cached(parent, name)) {
         if (&cached_custody->inode() != &inode) {
             dbgprintf("WTF! cached custody for name '%s' has inode=%s, new inode=%s\n",
                 name.characters(),
diff --git a/Kernel/FileSystem/Custody.h b/Kernel/FileSystem/Custody.h
index 03c6fabdff..cc2ca004f1 100644
--- a/Kernel/FileSystem/Custody.h
+++ b/Kernel/FileSystem/Custody.h
@@ -13,8 +13,8 @@ class VFS;
 class Custody : public RefCounted<Custody> {
 public:
     static Custody* get_if_cached(Custody* parent, const String& name);
-    static Retained<Custody> get_or_create(Custody* parent, const String& name, Inode&);
-    static Retained<Custody> create(Custody* parent, const String& name, Inode& inode)
+    static NonnullRefPtr<Custody> get_or_create(Custody* parent, const String& name, Inode&);
+    static NonnullRefPtr<Custody> create(Custody* parent, const String& name, Inode& inode)
     {
         return adopt(*new Custody(parent, name, inode));
     }
@@ -38,9 +38,9 @@ public:
 private:
     Custody(Custody* parent, const String& name, Inode&);
 
-    RetainPtr<Custody> m_parent;
+    RefPtr<Custody> m_parent;
     String m_name;
-    Retained<Inode> m_inode;
+    NonnullRefPtr<Inode> m_inode;
     bool m_deleted { false };
     bool m_mounted_on { false };
 };
diff --git a/Kernel/FileSystem/DevPtsFS.cpp b/Kernel/FileSystem/DevPtsFS.cpp
index be3a0d6968..d376192511 100644
--- a/Kernel/FileSystem/DevPtsFS.cpp
+++ b/Kernel/FileSystem/DevPtsFS.cpp
@@ -11,7 +11,7 @@ DevPtsFS& DevPtsFS::the()
     return *s_the;
 }
 
-Retained<DevPtsFS> DevPtsFS::create()
+NonnullRefPtr<DevPtsFS> DevPtsFS::create()
 {
     return adopt(*new DevPtsFS);
 }
@@ -36,7 +36,7 @@ const char* DevPtsFS::class_name() const
     return "DevPtsFS";
 }
 
-Retained<SynthFSInode> DevPtsFS::create_slave_pty_device_file(unsigned index)
+NonnullRefPtr<SynthFSInode> DevPtsFS::create_slave_pty_device_file(unsigned index)
 {
     auto file = adopt(*new SynthFSInode(*this, generate_inode_index()));
 
diff --git a/Kernel/FileSystem/DevPtsFS.h b/Kernel/FileSystem/DevPtsFS.h
index fc638bd580..b285814cf5 100644
--- a/Kernel/FileSystem/DevPtsFS.h
+++ b/Kernel/FileSystem/DevPtsFS.h
@@ -11,7 +11,7 @@ public:
     [[gnu::pure]] static DevPtsFS& the();
 
     virtual ~DevPtsFS() override;
-    static Retained<DevPtsFS> create();
+    static NonnullRefPtr<DevPtsFS> create();
 
     virtual bool initialize() override;
     virtual const char* class_name() const override;
@@ -22,7 +22,7 @@ public:
 private:
     DevPtsFS();
 
-    Retained<SynthFSInode> create_slave_pty_device_file(unsigned index);
+    NonnullRefPtr<SynthFSInode> create_slave_pty_device_file(unsigned index);
 
     HashTable<SlavePTY*> m_slave_ptys;
 };
diff --git a/Kernel/FileSystem/DiskBackedFileSystem.cpp b/Kernel/FileSystem/DiskBackedFileSystem.cpp
index 413e4931ed..afb4a8cc5f 100644
--- a/Kernel/FileSystem/DiskBackedFileSystem.cpp
+++ b/Kernel/FileSystem/DiskBackedFileSystem.cpp
@@ -45,7 +45,7 @@ Lockable<InlineLRUCache<BlockIdentifier, CachedBlock>>& block_cache()
     return *s_cache;
 }
 
-DiskBackedFS::DiskBackedFS(Retained<DiskDevice>&& device)
+DiskBackedFS::DiskBackedFS(NonnullRefPtr<DiskDevice>&& device)
     : m_device(move(device))
 {
 }
diff --git a/Kernel/FileSystem/DiskBackedFileSystem.h b/Kernel/FileSystem/DiskBackedFileSystem.h
index b115eb6d12..8f75435e71 100644
--- a/Kernel/FileSystem/DiskBackedFileSystem.h
+++ b/Kernel/FileSystem/DiskBackedFileSystem.h
@@ -15,7 +15,7 @@ public:
     virtual void flush_writes() override;
 
 protected:
-    explicit DiskBackedFS(Retained<DiskDevice>&&);
+    explicit DiskBackedFS(NonnullRefPtr<DiskDevice>&&);
 
     void set_block_size(unsigned);
 
@@ -27,7 +27,7 @@ protected:
 
 private:
     int m_block_size { 0 };
-    Retained<DiskDevice> m_device;
+    NonnullRefPtr<DiskDevice> m_device;
 
     HashMap<unsigned, ByteBuffer> m_write_cache;
 };
diff --git a/Kernel/FileSystem/Ext2FileSystem.cpp b/Kernel/FileSystem/Ext2FileSystem.cpp
index c9ea7b06bc..ce7cefcc48 100644
--- a/Kernel/FileSystem/Ext2FileSystem.cpp
+++ b/Kernel/FileSystem/Ext2FileSystem.cpp
@@ -31,12 +31,12 @@ static byte to_ext2_file_type(mode_t mode)
     return EXT2_FT_UNKNOWN;
 }
 
-Retained<Ext2FS> Ext2FS::create(Retained<DiskDevice>&& device)
+NonnullRefPtr<Ext2FS> Ext2FS::create(NonnullRefPtr<DiskDevice>&& device)
 {
     return adopt(*new Ext2FS(move(device)));
 }
 
-Ext2FS::Ext2FS(Retained<DiskDevice>&& device)
+Ext2FS::Ext2FS(NonnullRefPtr<DiskDevice>&& device)
     : DiskBackedFS(move(device))
 {
 }
@@ -448,7 +448,7 @@ void Ext2FSInode::flush_metadata()
     set_metadata_dirty(false);
 }
 
-RetainPtr<Inode> Ext2FS::get_inode(InodeIdentifier inode) const
+RefPtr<Inode> Ext2FS::get_inode(InodeIdentifier inode) const
 {
     LOCKER(m_lock);
     ASSERT(inode.fsid() == fsid());
@@ -1085,7 +1085,7 @@ bool Ext2FS::set_block_allocation_state(BlockIndex block_index, bool new_state)
     return true;
 }
 
-RetainPtr<Inode> Ext2FS::create_directory(InodeIdentifier parent_id, const String& name, mode_t mode, int& error)
+RefPtr<Inode> Ext2FS::create_directory(InodeIdentifier parent_id, const String& name, mode_t mode, int& error)
 {
     LOCKER(m_lock);
     ASSERT(parent_id.fsid() == fsid());
@@ -1125,7 +1125,7 @@ RetainPtr<Inode> Ext2FS::create_directory(InodeIdentifier parent_id, const Strin
     return inode;
 }
 
-RetainPtr<Inode> Ext2FS::create_inode(InodeIdentifier parent_id, const String& name, mode_t mode, off_t size, dev_t dev, int& error)
+RefPtr<Inode> Ext2FS::create_inode(InodeIdentifier parent_id, const String& name, mode_t mode, off_t size, dev_t dev, int& error)
 {
     LOCKER(m_lock);
     ASSERT(parent_id.fsid() == fsid());
diff --git a/Kernel/FileSystem/Ext2FileSystem.h b/Kernel/FileSystem/Ext2FileSystem.h
index 7ef3d10240..64349ee1a2 100644
--- a/Kernel/FileSystem/Ext2FileSystem.h
+++ b/Kernel/FileSystem/Ext2FileSystem.h
@@ -60,7 +60,7 @@ class Ext2FS final : public DiskBackedFS {
     friend class Ext2FSInode;
 
 public:
-    static Retained<Ext2FS> create(Retained<DiskDevice>&&);
+    static NonnullRefPtr<Ext2FS> create(NonnullRefPtr<DiskDevice>&&);
     virtual ~Ext2FS() override;
     virtual bool initialize() override;
 
@@ -73,7 +73,7 @@ private:
     typedef unsigned BlockIndex;
     typedef unsigned GroupIndex;
     typedef unsigned InodeIndex;
-    explicit Ext2FS(Retained<DiskDevice>&&);
+    explicit Ext2FS(NonnullRefPtr<DiskDevice>&&);
 
     const ext2_super_block& super_block() const;
     const ext2_group_desc& group_descriptor(unsigned groupIndex) const;
@@ -92,9 +92,9 @@ private:
 
     virtual const char* class_name() const override;
     virtual InodeIdentifier root_inode() const override;
-    virtual RetainPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) override;
-    virtual RetainPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) override;
-    virtual RetainPtr<Inode> get_inode(InodeIdentifier) const override;
+    virtual RefPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) override;
+    virtual RefPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) override;
+    virtual RefPtr<Inode> get_inode(InodeIdentifier) const override;
 
     InodeIndex allocate_inode(GroupIndex preferred_group, off_t expected_size);
     Vector<BlockIndex> allocate_blocks(GroupIndex, int count);
@@ -126,7 +126,7 @@ private:
     mutable ByteBuffer m_cached_super_block;
     mutable ByteBuffer m_cached_group_descriptor_table;
 
-    mutable HashMap<BlockIndex, RetainPtr<Ext2FSInode>> m_inode_cache;
+    mutable HashMap<BlockIndex, RefPtr<Ext2FSInode>> m_inode_cache;
 };
 
 inline Ext2FS& Ext2FSInode::fs()
diff --git a/Kernel/FileSystem/FIFO.cpp b/Kernel/FileSystem/FIFO.cpp
index 6e1f081848..c2d0184377 100644
--- a/Kernel/FileSystem/FIFO.cpp
+++ b/Kernel/FileSystem/FIFO.cpp
@@ -16,7 +16,7 @@ Lockable<HashTable<FIFO*>>& all_fifos()
     return *s_table;
 }
 
-RetainPtr<FIFO> FIFO::from_fifo_id(dword id)
+RefPtr<FIFO> FIFO::from_fifo_id(dword id)
 {
     auto* ptr = reinterpret_cast<FIFO*>(id);
     LOCKER(all_fifos().lock());
@@ -25,12 +25,12 @@ RetainPtr<FIFO> FIFO::from_fifo_id(dword id)
     return ptr;
 }
 
-Retained<FIFO> FIFO::create(uid_t uid)
+NonnullRefPtr<FIFO> FIFO::create(uid_t uid)
 {
     return adopt(*new FIFO(uid));
 }
 
-Retained<FileDescription> FIFO::open_direction(FIFO::Direction direction)
+NonnullRefPtr<FileDescription> FIFO::open_direction(FIFO::Direction direction)
 {
     auto description = FileDescription::create(this);
     attach(direction);
diff --git a/Kernel/FileSystem/FIFO.h b/Kernel/FileSystem/FIFO.h
index baad9bd8a1..73a3915ba0 100644
--- a/Kernel/FileSystem/FIFO.h
+++ b/Kernel/FileSystem/FIFO.h
@@ -14,14 +14,14 @@ public:
         Writer
     };
 
-    static RetainPtr<FIFO> from_fifo_id(dword);
+    static RefPtr<FIFO> from_fifo_id(dword);
 
-    static Retained<FIFO> create(uid_t);
+    static NonnullRefPtr<FIFO> create(uid_t);
     virtual ~FIFO() override;
 
     uid_t uid() const { return m_uid; }
 
-    Retained<FileDescription> open_direction(Direction);
+    NonnullRefPtr<FileDescription> open_direction(Direction);
 
     void attach(Direction);
     void detach(Direction);
diff --git a/Kernel/FileSystem/FileDescription.cpp b/Kernel/FileSystem/FileDescription.cpp
index a75ec14259..d6c75a8fb6 100644
--- a/Kernel/FileSystem/FileDescription.cpp
+++ b/Kernel/FileSystem/FileDescription.cpp
@@ -15,19 +15,19 @@
 #include <Kernel/VM/MemoryManager.h>
 #include <LibC/errno_numbers.h>
 
-Retained<FileDescription> FileDescription::create(RetainPtr<Custody>&& custody)
+NonnullRefPtr<FileDescription> FileDescription::create(RefPtr<Custody>&& custody)
 {
     auto description = adopt(*new FileDescription(InodeFile::create(custody->inode())));
     description->m_custody = move(custody);
     return description;
 }
 
-Retained<FileDescription> FileDescription::create(RetainPtr<File>&& file, SocketRole role)
+NonnullRefPtr<FileDescription> FileDescription::create(RefPtr<File>&& file, SocketRole role)
 {
     return adopt(*new FileDescription(move(file), role));
 }
 
-FileDescription::FileDescription(RetainPtr<File>&& file, SocketRole role)
+FileDescription::FileDescription(RefPtr<File>&& file, SocketRole role)
     : m_file(move(file))
 {
     if (m_file->is_inode())
@@ -58,9 +58,9 @@ void FileDescription::set_socket_role(SocketRole role)
     socket()->attach(*this);
 }
 
-Retained<FileDescription> FileDescription::clone()
+NonnullRefPtr<FileDescription> FileDescription::clone()
 {
-    RetainPtr<FileDescription> description;
+    RefPtr<FileDescription> description;
     if (is_fifo()) {
         description = fifo()->open_direction(m_fifo_direction);
     } else {
diff --git a/Kernel/FileSystem/FileDescription.h b/Kernel/FileSystem/FileDescription.h
index 2cffc5169a..b856eff045 100644
--- a/Kernel/FileSystem/FileDescription.h
+++ b/Kernel/FileSystem/FileDescription.h
@@ -21,11 +21,11 @@ class SharedMemory;
 
 class FileDescription : public RefCounted<FileDescription> {
 public:
-    static Retained<FileDescription> create(RetainPtr<Custody>&&);
-    static Retained<FileDescription> create(RetainPtr<File>&&, SocketRole = SocketRole::None);
+    static NonnullRefPtr<FileDescription> create(RefPtr<Custody>&&);
+    static NonnullRefPtr<FileDescription> create(RefPtr<File>&&, SocketRole = SocketRole::None);
     ~FileDescription();
 
-    Retained<FileDescription> clone();
+    NonnullRefPtr<FileDescription> clone();
 
     int close();
 
@@ -92,7 +92,7 @@ public:
 
     ByteBuffer& generator_cache() { return m_generator_cache; }
 
-    void set_original_inode(Badge<VFS>, Retained<Inode>&& inode) { m_inode = move(inode); }
+    void set_original_inode(Badge<VFS>, NonnullRefPtr<Inode>&& inode) { m_inode = move(inode); }
 
     SocketRole socket_role() const { return m_socket_role; }
     void set_socket_role(SocketRole);
@@ -105,12 +105,12 @@ public:
 
 private:
     friend class VFS;
-    FileDescription(RetainPtr<File>&&, SocketRole = SocketRole::None);
+    FileDescription(RefPtr<File>&&, SocketRole = SocketRole::None);
     FileDescription(FIFO&, FIFO::Direction);
 
-    RetainPtr<Custody> m_custody;
-    RetainPtr<Inode> m_inode;
-    RetainPtr<File> m_file;
+    RefPtr<Custody> m_custody;
+    RefPtr<Inode> m_inode;
+    RefPtr<File> m_file;
 
     off_t m_current_offset { 0 };
 
diff --git a/Kernel/FileSystem/FileSystem.cpp b/Kernel/FileSystem/FileSystem.cpp
index 95a4f47093..885087fbef 100644
--- a/Kernel/FileSystem/FileSystem.cpp
+++ b/Kernel/FileSystem/FileSystem.cpp
@@ -58,7 +58,7 @@ void FS::sync()
 {
     Inode::sync();
 
-    Vector<Retained<FS>, 32> fses;
+    Vector<NonnullRefPtr<FS>, 32> fses;
     {
         InterruptDisabler disabler;
         for (auto& it : all_fses())
diff --git a/Kernel/FileSystem/FileSystem.h b/Kernel/FileSystem/FileSystem.h
index 3e9fcc6314..c9ad4b5dcb 100644
--- a/Kernel/FileSystem/FileSystem.h
+++ b/Kernel/FileSystem/FileSystem.h
@@ -54,10 +54,10 @@ public:
         byte file_type { 0 };
     };
 
-    virtual RetainPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) = 0;
-    virtual RetainPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) = 0;
+    virtual RefPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) = 0;
+    virtual RefPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) = 0;
 
-    virtual RetainPtr<Inode> get_inode(InodeIdentifier) const = 0;
+    virtual RefPtr<Inode> get_inode(InodeIdentifier) const = 0;
 
     virtual void flush_writes() {}
 
diff --git a/Kernel/FileSystem/Inode.cpp b/Kernel/FileSystem/Inode.cpp
index ef4fbe8207..57cd4af8e1 100644
--- a/Kernel/FileSystem/Inode.cpp
+++ b/Kernel/FileSystem/Inode.cpp
@@ -13,7 +13,7 @@ HashTable<Inode*>& all_inodes()
 
 void Inode::sync()
 {
-    Vector<Retained<Inode>, 32> inodes;
+    Vector<NonnullRefPtr<Inode>, 32> inodes;
     {
         InterruptDisabler disabler;
         for (auto* inode : all_inodes()) {
diff --git a/Kernel/FileSystem/Inode.h b/Kernel/FileSystem/Inode.h
index c7d3baf274..f3b769710f 100644
--- a/Kernel/FileSystem/Inode.h
+++ b/Kernel/FileSystem/Inode.h
@@ -85,6 +85,6 @@ private:
     FS& m_fs;
     unsigned m_index { 0 };
     WeakPtr<VMObject> m_vmo;
-    RetainPtr<LocalSocket> m_socket;
+    RefPtr<LocalSocket> m_socket;
     bool m_metadata_dirty { false };
 };
diff --git a/Kernel/FileSystem/InodeFile.cpp b/Kernel/FileSystem/InodeFile.cpp
index 5dee202e68..7617636486 100644
--- a/Kernel/FileSystem/InodeFile.cpp
+++ b/Kernel/FileSystem/InodeFile.cpp
@@ -4,7 +4,7 @@
 #include <Kernel/FileSystem/VirtualFileSystem.h>
 #include <Kernel/Process.h>
 
-InodeFile::InodeFile(Retained<Inode>&& inode)
+InodeFile::InodeFile(NonnullRefPtr<Inode>&& inode)
     : m_inode(move(inode))
 {
 }
diff --git a/Kernel/FileSystem/InodeFile.h b/Kernel/FileSystem/InodeFile.h
index 73f1f2444f..f4bbe7b48d 100644
--- a/Kernel/FileSystem/InodeFile.h
+++ b/Kernel/FileSystem/InodeFile.h
@@ -6,7 +6,7 @@ class Inode;
 
 class InodeFile final : public File {
 public:
-    static Retained<InodeFile> create(Retained<Inode>&& inode)
+    static NonnullRefPtr<InodeFile> create(NonnullRefPtr<Inode>&& inode)
     {
         return adopt(*new InodeFile(move(inode)));
     }
@@ -33,6 +33,6 @@ public:
     virtual bool is_inode() const override { return true; }
 
 private:
-    explicit InodeFile(Retained<Inode>&&);
-    Retained<Inode> m_inode;
+    explicit InodeFile(NonnullRefPtr<Inode>&&);
+    NonnullRefPtr<Inode> m_inode;
 };
diff --git a/Kernel/FileSystem/ProcFS.cpp b/Kernel/FileSystem/ProcFS.cpp
index 95ad22096b..06f6cb3f1d 100644
--- a/Kernel/FileSystem/ProcFS.cpp
+++ b/Kernel/FileSystem/ProcFS.cpp
@@ -174,7 +174,7 @@ ProcFS& ProcFS::the()
     return *s_the;
 }
 
-Retained<ProcFS> ProcFS::create()
+NonnullRefPtr<ProcFS> ProcFS::create()
 {
     return adopt(*new ProcFS);
 }
@@ -614,7 +614,7 @@ ByteBuffer procfs$inodes(InodeIdentifier)
     extern HashTable<Inode*>& all_inodes();
     StringBuilder builder;
     for (auto it : all_inodes()) {
-        RetainPtr<Inode> inode = *it;
+        RefPtr<Inode> inode = *it;
         builder.appendf("Inode{K%x} %02u:%08u (%u)\n", inode.ptr(), inode->fsid(), inode->index(), inode->ref_count());
     }
     return builder.to_byte_buffer();
@@ -747,13 +747,13 @@ const char* ProcFS::class_name() const
     return "ProcFS";
 }
 
-RetainPtr<Inode> ProcFS::create_inode(InodeIdentifier, const String&, mode_t, off_t, dev_t, int&)
+RefPtr<Inode> ProcFS::create_inode(InodeIdentifier, const String&, mode_t, off_t, dev_t, int&)
 {
     kprintf("FIXME: Implement ProcFS::create_inode()?\n");
     return {};
 }
 
-RetainPtr<Inode> ProcFS::create_directory(InodeIdentifier, const String&, mode_t, int& error)
+RefPtr<Inode> ProcFS::create_directory(InodeIdentifier, const String&, mode_t, int& error)
 {
     error = -EROFS;
     return nullptr;
@@ -764,7 +764,7 @@ InodeIdentifier ProcFS::root_inode() const
     return { fsid(), FI_Root };
 }
 
-RetainPtr<Inode> ProcFS::get_inode(InodeIdentifier inode_id) const
+RefPtr<Inode> ProcFS::get_inode(InodeIdentifier inode_id) const
 {
 #ifdef PROCFS_DEBUG
     dbgprintf("ProcFS::get_inode(%u)\n", inode_id.index());
diff --git a/Kernel/FileSystem/ProcFS.h b/Kernel/FileSystem/ProcFS.h
index 5b3e82969c..2976253556 100644
--- a/Kernel/FileSystem/ProcFS.h
+++ b/Kernel/FileSystem/ProcFS.h
@@ -16,16 +16,16 @@ public:
     [[gnu::pure]] static ProcFS& the();
 
     virtual ~ProcFS() override;
-    static Retained<ProcFS> create();
+    static NonnullRefPtr<ProcFS> create();
 
     virtual bool initialize() override;
     virtual const char* class_name() const override;
 
     virtual InodeIdentifier root_inode() const override;
-    virtual RetainPtr<Inode> get_inode(InodeIdentifier) const override;
+    virtual RefPtr<Inode> get_inode(InodeIdentifier) const override;
 
-    virtual RetainPtr<Inode> create_inode(InodeIdentifier parent_id, const String& name, mode_t, off_t size, dev_t, int& error) override;
-    virtual RetainPtr<Inode> create_directory(InodeIdentifier parent_id, const String& name, mode_t, int& error) override;
+    virtual RefPtr<Inode> create_inode(InodeIdentifier parent_id, const String& name, mode_t, off_t size, dev_t, int& error) override;
+    virtual RefPtr<Inode> create_directory(InodeIdentifier parent_id, const String& name, mode_t, int& error) override;
 
     void add_sys_file(String&&, Function<ByteBuffer(ProcFSInode&)>&& read_callback, Function<ssize_t(ProcFSInode&, const ByteBuffer&)>&& write_callback);
     void add_sys_bool(String&&, Lockable<bool>&, Function<void()>&& notify_callback = nullptr);
@@ -36,7 +36,7 @@ private:
 
     struct ProcFSDirectoryEntry {
         ProcFSDirectoryEntry() {}
-        ProcFSDirectoryEntry(const char* a_name, unsigned a_proc_file_type, Function<ByteBuffer(InodeIdentifier)>&& a_read_callback = nullptr, Function<ssize_t(InodeIdentifier, const ByteBuffer&)>&& a_write_callback = nullptr, RetainPtr<ProcFSInode>&& a_inode = nullptr)
+        ProcFSDirectoryEntry(const char* a_name, unsigned a_proc_file_type, Function<ByteBuffer(InodeIdentifier)>&& a_read_callback = nullptr, Function<ssize_t(InodeIdentifier, const ByteBuffer&)>&& a_write_callback = nullptr, RefPtr<ProcFSInode>&& a_inode = nullptr)
             : name(a_name)
             , proc_file_type(a_proc_file_type)
             , read_callback(move(a_read_callback))
@@ -49,7 +49,7 @@ private:
         unsigned proc_file_type { 0 };
         Function<ByteBuffer(InodeIdentifier)> read_callback;
         Function<ssize_t(InodeIdentifier, const ByteBuffer&)> write_callback;
-        RetainPtr<ProcFSInode> inode;
+        RefPtr<ProcFSInode> inode;
         InodeIdentifier identifier(unsigned fsid) const;
     };
 
@@ -60,7 +60,7 @@ private:
 
     mutable Lock m_inodes_lock;
     mutable HashMap<unsigned, ProcFSInode*> m_inodes;
-    RetainPtr<ProcFSInode> m_root_inode;
+    RefPtr<ProcFSInode> m_root_inode;
     Lockable<bool> m_kmalloc_stack_helper;
 };
 
diff --git a/Kernel/FileSystem/SyntheticFileSystem.cpp b/Kernel/FileSystem/SyntheticFileSystem.cpp
index 62ea9c55fd..d884fd0e3d 100644
--- a/Kernel/FileSystem/SyntheticFileSystem.cpp
+++ b/Kernel/FileSystem/SyntheticFileSystem.cpp
@@ -5,7 +5,7 @@
 
 //#define SYNTHFS_DEBUG
 
-Retained<SynthFS> SynthFS::create()
+NonnullRefPtr<SynthFS> SynthFS::create()
 {
     return adopt(*new SynthFS);
 }
@@ -33,7 +33,7 @@ bool SynthFS::initialize()
     return true;
 }
 
-Retained<SynthFSInode> SynthFS::create_directory(String&& name)
+NonnullRefPtr<SynthFSInode> SynthFS::create_directory(String&& name)
 {
     auto file = adopt(*new SynthFSInode(*this, generate_inode_index()));
     file->m_name = move(name);
@@ -45,7 +45,7 @@ Retained<SynthFSInode> SynthFS::create_directory(String&& name)
     return file;
 }
 
-Retained<SynthFSInode> SynthFS::create_text_file(String&& name, ByteBuffer&& contents, mode_t mode)
+NonnullRefPtr<SynthFSInode> SynthFS::create_text_file(String&& name, ByteBuffer&& contents, mode_t mode)
 {
     auto file = adopt(*new SynthFSInode(*this, generate_inode_index()));
     file->m_data = contents;
@@ -58,7 +58,7 @@ Retained<SynthFSInode> SynthFS::create_text_file(String&& name, ByteBuffer&& con
     return file;
 }
 
-Retained<SynthFSInode> SynthFS::create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&& generator, mode_t mode)
+NonnullRefPtr<SynthFSInode> SynthFS::create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&& generator, mode_t mode)
 {
     auto file = adopt(*new SynthFSInode(*this, generate_inode_index()));
     file->m_generator = move(generator);
@@ -71,7 +71,7 @@ Retained<SynthFSInode> SynthFS::create_generated_file(String&& name, Function<By
     return file;
 }
 
-Retained<SynthFSInode> SynthFS::create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&& read_callback, Function<ssize_t(SynthFSInode&, const ByteBuffer&)>&& write_callback, mode_t mode)
+NonnullRefPtr<SynthFSInode> SynthFS::create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&& read_callback, Function<ssize_t(SynthFSInode&, const ByteBuffer&)>&& write_callback, mode_t mode)
 {
     auto file = adopt(*new SynthFSInode(*this, generate_inode_index()));
     file->m_generator = move(read_callback);
@@ -85,7 +85,7 @@ Retained<SynthFSInode> SynthFS::create_generated_file(String&& name, Function<By
     return file;
 }
 
-InodeIdentifier SynthFS::add_file(RetainPtr<SynthFSInode>&& file, InodeIndex parent)
+InodeIdentifier SynthFS::add_file(RefPtr<SynthFSInode>&& file, InodeIndex parent)
 {
     LOCKER(m_lock);
     ASSERT(file);
@@ -138,7 +138,7 @@ InodeIdentifier SynthFS::root_inode() const
     return { fsid(), 1 };
 }
 
-RetainPtr<Inode> SynthFS::create_inode(InodeIdentifier parentInode, const String& name, mode_t mode, off_t size, dev_t, int& error)
+RefPtr<Inode> SynthFS::create_inode(InodeIdentifier parentInode, const String& name, mode_t mode, off_t size, dev_t, int& error)
 {
     (void)parentInode;
     (void)name;
@@ -149,7 +149,7 @@ RetainPtr<Inode> SynthFS::create_inode(InodeIdentifier parentInode, const String
     return {};
 }
 
-RetainPtr<Inode> SynthFS::create_directory(InodeIdentifier, const String&, mode_t, int& error)
+RefPtr<Inode> SynthFS::create_directory(InodeIdentifier, const String&, mode_t, int& error)
 {
     error = -EROFS;
     return nullptr;
@@ -161,7 +161,7 @@ auto SynthFS::generate_inode_index() -> InodeIndex
     return m_next_inode_index++;
 }
 
-RetainPtr<Inode> SynthFS::get_inode(InodeIdentifier inode) const
+RefPtr<Inode> SynthFS::get_inode(InodeIdentifier inode) const
 {
     LOCKER(m_lock);
     auto it = m_inodes.find(inode.index());
diff --git a/Kernel/FileSystem/SyntheticFileSystem.h b/Kernel/FileSystem/SyntheticFileSystem.h
index 5a46f85a87..15e5dc9a21 100644
--- a/Kernel/FileSystem/SyntheticFileSystem.h
+++ b/Kernel/FileSystem/SyntheticFileSystem.h
@@ -10,14 +10,14 @@ class SynthFSInode;
 class SynthFS : public FS {
 public:
     virtual ~SynthFS() override;
-    static Retained<SynthFS> create();
+    static NonnullRefPtr<SynthFS> create();
 
     virtual bool initialize() override;
     virtual const char* class_name() const override;
     virtual InodeIdentifier root_inode() const override;
-    virtual RetainPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) override;
-    virtual RetainPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) override;
-    virtual RetainPtr<Inode> get_inode(InodeIdentifier) const override;
+    virtual RefPtr<Inode> create_inode(InodeIdentifier parentInode, const String& name, mode_t, off_t size, dev_t, int& error) override;
+    virtual RefPtr<Inode> create_directory(InodeIdentifier parentInode, const String& name, mode_t, int& error) override;
+    virtual RefPtr<Inode> get_inode(InodeIdentifier) const override;
 
 protected:
     typedef unsigned InodeIndex;
@@ -27,17 +27,17 @@ protected:
 
     SynthFS();
 
-    Retained<SynthFSInode> create_directory(String&& name);
-    Retained<SynthFSInode> create_text_file(String&& name, ByteBuffer&&, mode_t = 0010644);
-    Retained<SynthFSInode> create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&&, mode_t = 0100644);
-    Retained<SynthFSInode> create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&&, Function<ssize_t(SynthFSInode&, const ByteBuffer&)>&&, mode_t = 0100644);
+    NonnullRefPtr<SynthFSInode> create_directory(String&& name);
+    NonnullRefPtr<SynthFSInode> create_text_file(String&& name, ByteBuffer&&, mode_t = 0010644);
+    NonnullRefPtr<SynthFSInode> create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&&, mode_t = 0100644);
+    NonnullRefPtr<SynthFSInode> create_generated_file(String&& name, Function<ByteBuffer(SynthFSInode&)>&&, Function<ssize_t(SynthFSInode&, const ByteBuffer&)>&&, mode_t = 0100644);
 
-    InodeIdentifier add_file(RetainPtr<SynthFSInode>&&, InodeIndex parent = RootInodeIndex);
+    InodeIdentifier add_file(RefPtr<SynthFSInode>&&, InodeIndex parent = RootInodeIndex);
     bool remove_file(InodeIndex);
 
 private:
     InodeIndex m_next_inode_index { 2 };
-    HashMap<InodeIndex, RetainPtr<SynthFSInode>> m_inodes;
+    HashMap<InodeIndex, RefPtr<SynthFSInode>> m_inodes;
 };
 
 struct SynthFSInodeCustomData {
diff --git a/Kernel/FileSystem/VirtualFileSystem.cpp b/Kernel/FileSystem/VirtualFileSystem.cpp
index 296821094e..9d0b126813 100644
--- a/Kernel/FileSystem/VirtualFileSystem.cpp
+++ b/Kernel/FileSystem/VirtualFileSystem.cpp
@@ -36,7 +36,7 @@ InodeIdentifier VFS::root_inode_id() const
     return m_root_inode->identifier();
 }
 
-bool VFS::mount(Retained<FS>&& file_system, StringView path)
+bool VFS::mount(NonnullRefPtr<FS>&& file_system, StringView path)
 {
     auto result = resolve_path(path, root_custody());
     if (result.is_error()) {
@@ -53,7 +53,7 @@ bool VFS::mount(Retained<FS>&& file_system, StringView path)
     return true;
 }
 
-bool VFS::mount_root(Retained<FS>&& file_system)
+bool VFS::mount_root(NonnullRefPtr<FS>&& file_system)
 {
     if (m_root_inode) {
         kprintf("VFS: mount_root can't mount another root\n");
@@ -149,9 +149,9 @@ KResult VFS::stat(StringView path, int options, Custody& base, struct stat& stat
     return custody_or_error.value()->inode().metadata().stat(statbuf);
 }
 
-KResultOr<Retained<FileDescription>> VFS::open(StringView path, int options, mode_t mode, Custody& base)
+KResultOr<NonnullRefPtr<FileDescription>> VFS::open(StringView path, int options, mode_t mode, Custody& base)
 {
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto custody_or_error = resolve_path(path, base, &parent_custody, options);
     if (options & O_CREAT) {
         if (!parent_custody)
@@ -208,7 +208,7 @@ KResult VFS::mknod(StringView path, mode_t mode, dev_t dev, Custody& base)
     if (!is_regular_file(mode) && !is_block_device(mode) && !is_character_device(mode) && !is_fifo(mode) && !is_socket(mode))
         return KResult(-EINVAL);
 
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto existing_file_or_error = resolve_path(path, base, &parent_custody);
     if (!existing_file_or_error.is_error())
         return KResult(-EEXIST);
@@ -230,7 +230,7 @@ KResult VFS::mknod(StringView path, mode_t mode, dev_t dev, Custody& base)
     return KSuccess;
 }
 
-KResultOr<Retained<FileDescription>> VFS::create(StringView path, int options, mode_t mode, Custody& parent_custody)
+KResultOr<NonnullRefPtr<FileDescription>> VFS::create(StringView path, int options, mode_t mode, Custody& parent_custody)
 {
     (void)options;
 
@@ -255,7 +255,7 @@ KResultOr<Retained<FileDescription>> VFS::create(StringView path, int options, m
 
 KResult VFS::mkdir(StringView path, mode_t mode, Custody& base)
 {
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto result = resolve_path(path, base, &parent_custody);
     if (!result.is_error())
         return KResult(-EEXIST);
@@ -300,7 +300,7 @@ KResult VFS::access(StringView path, int mode, Custody& base)
     return KSuccess;
 }
 
-KResultOr<Retained<Custody>> VFS::open_directory(StringView path, Custody& base)
+KResultOr<NonnullRefPtr<Custody>> VFS::open_directory(StringView path, Custody& base)
 {
     auto inode_or_error = resolve_path(path, base);
     if (inode_or_error.is_error())
@@ -339,14 +339,14 @@ KResult VFS::chmod(StringView path, mode_t mode, Custody& base)
 
 KResult VFS::rename(StringView old_path, StringView new_path, Custody& base)
 {
-    RetainPtr<Custody> old_parent_custody;
+    RefPtr<Custody> old_parent_custody;
     auto old_custody_or_error = resolve_path(old_path, base, &old_parent_custody);
     if (old_custody_or_error.is_error())
         return old_custody_or_error.error();
     auto& old_custody = *old_custody_or_error.value();
     auto& old_inode = old_custody.inode();
 
-    RetainPtr<Custody> new_parent_custody;
+    RefPtr<Custody> new_parent_custody;
     auto new_custody_or_error = resolve_path(new_path, base, &new_parent_custody);
     if (new_custody_or_error.is_error()) {
         if (new_custody_or_error.error() != -ENOENT)
@@ -445,7 +445,7 @@ KResult VFS::link(StringView old_path, StringView new_path, Custody& base)
     auto& old_custody = *old_custody_or_error.value();
     auto& old_inode = old_custody.inode();
 
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto new_custody_or_error = resolve_path(new_path, base, &parent_custody);
     if (!new_custody_or_error.is_error())
         return KResult(-EEXIST);
@@ -469,7 +469,7 @@ KResult VFS::link(StringView old_path, StringView new_path, Custody& base)
 
 KResult VFS::unlink(StringView path, Custody& base)
 {
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto custody_or_error = resolve_path(path, base, &parent_custody);
     if (custody_or_error.is_error())
         return custody_or_error.error();
@@ -498,7 +498,7 @@ KResult VFS::unlink(StringView path, Custody& base)
 
 KResult VFS::symlink(StringView target, StringView linkpath, Custody& base)
 {
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto existing_custody_or_error = resolve_path(linkpath, base, &parent_custody);
     if (!existing_custody_or_error.is_error())
         return KResult(-EEXIST);
@@ -524,7 +524,7 @@ KResult VFS::symlink(StringView target, StringView linkpath, Custody& base)
 
 KResult VFS::rmdir(StringView path, Custody& base)
 {
-    RetainPtr<Custody> parent_custody;
+    RefPtr<Custody> parent_custody;
     auto custody_or_error = resolve_path(path, base, &parent_custody);
     if (custody_or_error.is_error())
         return KResult(custody_or_error.error());
@@ -559,14 +559,14 @@ KResult VFS::rmdir(StringView path, Custody& base)
     return parent_inode.remove_child(FileSystemPath(path).basename());
 }
 
-RetainPtr<Inode> VFS::get_inode(InodeIdentifier inode_id)
+RefPtr<Inode> VFS::get_inode(InodeIdentifier inode_id)
 {
     if (!inode_id.is_valid())
         return nullptr;
     return inode_id.fs()->get_inode(inode_id);
 }
 
-VFS::Mount::Mount(RetainPtr<Custody>&& host_custody, Retained<FS>&& guest_fs)
+VFS::Mount::Mount(RefPtr<Custody>&& host_custody, NonnullRefPtr<FS>&& guest_fs)
     : m_guest(guest_fs->root_inode())
     , m_guest_fs(move(guest_fs))
     , m_host_custody(move(host_custody))
@@ -624,7 +624,7 @@ Custody& VFS::root_custody()
     return *m_root_custody;
 }
 
-KResultOr<Retained<Custody>> VFS::resolve_path(StringView path, Custody& base, RetainPtr<Custody>* parent_custody, int options)
+KResultOr<NonnullRefPtr<Custody>> VFS::resolve_path(StringView path, Custody& base, RefPtr<Custody>* parent_custody, int options)
 {
     if (path.is_empty())
         return KResult(-EINVAL);
@@ -632,7 +632,7 @@ KResultOr<Retained<Custody>> VFS::resolve_path(StringView path, Custody& base, R
     auto parts = path.split_view('/');
     InodeIdentifier crumb_id;
 
-    Vector<Retained<Custody>, 32> custody_chain;
+    Vector<NonnullRefPtr<Custody>, 32> custody_chain;
 
     if (path[0] == '/') {
         custody_chain.append(root_custody());
diff --git a/Kernel/FileSystem/VirtualFileSystem.h b/Kernel/FileSystem/VirtualFileSystem.h
index c1f2e20860..595e75cb86 100644
--- a/Kernel/FileSystem/VirtualFileSystem.h
+++ b/Kernel/FileSystem/VirtualFileSystem.h
@@ -35,7 +35,7 @@ class VFS {
 public:
     class Mount {
     public:
-        Mount(RetainPtr<Custody>&&, Retained<FS>&&);
+        Mount(RefPtr<Custody>&&, NonnullRefPtr<FS>&&);
 
         InodeIdentifier host() const;
         InodeIdentifier guest() const { return m_guest; }
@@ -47,8 +47,8 @@ public:
     private:
         InodeIdentifier m_host;
         InodeIdentifier m_guest;
-        Retained<FS> m_guest_fs;
-        RetainPtr<Custody> m_host_custody;
+        NonnullRefPtr<FS> m_guest_fs;
+        RefPtr<Custody> m_host_custody;
     };
 
     [[gnu::pure]] static VFS& the();
@@ -56,12 +56,12 @@ public:
     VFS();
     ~VFS();
 
-    bool mount_root(Retained<FS>&&);
-    bool mount(Retained<FS>&&, StringView path);
+    bool mount_root(NonnullRefPtr<FS>&&);
+    bool mount(NonnullRefPtr<FS>&&, StringView path);
 
-    KResultOr<Retained<FileDescription>> open(RetainPtr<Device>&&, int options);
-    KResultOr<Retained<FileDescription>> open(StringView path, int options, mode_t mode, Custody& base);
-    KResultOr<Retained<FileDescription>> create(StringView path, int options, mode_t mode, Custody& parent_custody);
+    KResultOr<NonnullRefPtr<FileDescription>> open(RefPtr<Device>&&, int options);
+    KResultOr<NonnullRefPtr<FileDescription>> open(StringView path, int options, mode_t mode, Custody& base);
+    KResultOr<NonnullRefPtr<FileDescription>> create(StringView path, int options, mode_t mode, Custody& parent_custody);
     KResult mkdir(StringView path, mode_t mode, Custody& base);
     KResult link(StringView old_path, StringView new_path, Custody& base);
     KResult unlink(StringView path, Custody& base);
@@ -76,7 +76,7 @@ public:
     KResult utime(StringView path, Custody& base, time_t atime, time_t mtime);
     KResult rename(StringView oldpath, StringView newpath, Custody& base);
     KResult mknod(StringView path, mode_t, dev_t, Custody& base);
-    KResultOr<Retained<Custody>> open_directory(StringView path, Custody& base);
+    KResultOr<NonnullRefPtr<Custody>> open_directory(StringView path, Custody& base);
 
     void register_device(Badge<Device>, Device&);
     void unregister_device(Badge<Device>, Device&);
@@ -91,12 +91,12 @@ public:
     Device* get_device(unsigned major, unsigned minor);
 
     Custody& root_custody();
-    KResultOr<Retained<Custody>> resolve_path(StringView path, Custody& base, RetainPtr<Custody>* parent = nullptr, int options = 0);
+    KResultOr<NonnullRefPtr<Custody>> resolve_path(StringView path, Custody& base, RefPtr<Custody>* parent = nullptr, int options = 0);
 
 private:
     friend class FileDescription;
 
-    RetainPtr<Inode> get_inode(InodeIdentifier);
+    RefPtr<Inode> get_inode(InodeIdentifier);
 
     bool is_vfs_root(InodeIdentifier) const;
 
@@ -105,9 +105,9 @@ private:
     Mount* find_mount_for_host(InodeIdentifier);
     Mount* find_mount_for_guest(InodeIdentifier);
 
-    RetainPtr<Inode> m_root_inode;
+    RefPtr<Inode> m_root_inode;
     Vector<OwnPtr<Mount>> m_mounts;
     HashMap<dword, Device*> m_devices;
 
-    RetainPtr<Custody> m_root_custody;
+    RefPtr<Custody> m_root_custody;
 };
diff --git a/Kernel/Net/IPv4Socket.cpp b/Kernel/Net/IPv4Socket.cpp
index 0b205b191a..95ea2a4d19 100644
--- a/Kernel/Net/IPv4Socket.cpp
+++ b/Kernel/Net/IPv4Socket.cpp
@@ -23,7 +23,7 @@ Lockable<HashTable<IPv4Socket*>>& IPv4Socket::all_sockets()
     return *s_table;
 }
 
-Retained<IPv4Socket> IPv4Socket::create(int type, int protocol)
+NonnullRefPtr<IPv4Socket> IPv4Socket::create(int type, int protocol)
 {
     if (type == SOCK_STREAM)
         return TCPSocket::create(protocol);
diff --git a/Kernel/Net/IPv4Socket.h b/Kernel/Net/IPv4Socket.h
index dea6b5c171..e983bf8bc3 100644
--- a/Kernel/Net/IPv4Socket.h
+++ b/Kernel/Net/IPv4Socket.h
@@ -15,7 +15,7 @@ class TCPSocket;
 
 class IPv4Socket : public Socket {
 public:
-    static Retained<IPv4Socket> create(int type, int protocol);
+    static NonnullRefPtr<IPv4Socket> create(int type, int protocol);
     virtual ~IPv4Socket() override;
 
     static Lockable<HashTable<IPv4Socket*>>& all_sockets();
@@ -88,7 +88,7 @@ class IPv4SocketHandle : public SocketHandle {
 public:
     IPv4SocketHandle() {}
 
-    IPv4SocketHandle(RetainPtr<IPv4Socket>&& socket)
+    IPv4SocketHandle(RefPtr<IPv4Socket>&& socket)
         : SocketHandle(move(socket))
     {
     }
diff --git a/Kernel/Net/LocalSocket.cpp b/Kernel/Net/LocalSocket.cpp
index 95fcc6b940..57e13a4a3a 100644
--- a/Kernel/Net/LocalSocket.cpp
+++ b/Kernel/Net/LocalSocket.cpp
@@ -7,7 +7,7 @@
 
 //#define DEBUG_LOCAL_SOCKET
 
-Retained<LocalSocket> LocalSocket::create(int type)
+NonnullRefPtr<LocalSocket> LocalSocket::create(int type)
 {
     return adopt(*new LocalSocket(type));
 }
diff --git a/Kernel/Net/LocalSocket.h b/Kernel/Net/LocalSocket.h
index f1ac23719b..4d348e8435 100644
--- a/Kernel/Net/LocalSocket.h
+++ b/Kernel/Net/LocalSocket.h
@@ -7,7 +7,7 @@ class FileDescription;
 
 class LocalSocket final : public Socket {
 public:
-    static Retained<LocalSocket> create(int type);
+    static NonnullRefPtr<LocalSocket> create(int type);
     virtual ~LocalSocket() override;
 
     virtual KResult bind(const sockaddr*, socklen_t) override;
@@ -28,7 +28,7 @@ private:
     virtual bool is_local() const override { return true; }
     bool has_attached_peer(const FileDescription&) const;
 
-    RetainPtr<FileDescription> m_file;
+    RefPtr<FileDescription> m_file;
 
     bool m_bound { false };
     int m_accepted_fds_open { 0 };
diff --git a/Kernel/Net/NetworkTask.cpp b/Kernel/Net/NetworkTask.cpp
index 6113d241dd..0a12ffd5b7 100644
--- a/Kernel/Net/NetworkTask.cpp
+++ b/Kernel/Net/NetworkTask.cpp
@@ -209,7 +209,7 @@ void handle_icmp(const EthernetFrameHeader& eth, int frame_size)
 
     {
         LOCKER(IPv4Socket::all_sockets().lock());
-        for (RetainPtr<IPv4Socket> socket : IPv4Socket::all_sockets().resource()) {
+        for (RefPtr<IPv4Socket> socket : IPv4Socket::all_sockets().resource()) {
             LOCKER(socket->lock());
             if (socket->protocol() != (unsigned)IPv4Protocol::ICMP)
                 continue;
diff --git a/Kernel/Net/Socket.cpp b/Kernel/Net/Socket.cpp
index 6164cbe783..d15bd5d09b 100644
--- a/Kernel/Net/Socket.cpp
+++ b/Kernel/Net/Socket.cpp
@@ -6,7 +6,7 @@
 #include <Kernel/UnixTypes.h>
 #include <LibC/errno_numbers.h>
 
-KResultOr<Retained<Socket>> Socket::create(int domain, int type, int protocol)
+KResultOr<NonnullRefPtr<Socket>> Socket::create(int domain, int type, int protocol)
 {
     (void)protocol;
     switch (domain) {
@@ -41,7 +41,7 @@ KResult Socket::listen(int backlog)
     return KSuccess;
 }
 
-RetainPtr<Socket> Socket::accept()
+RefPtr<Socket> Socket::accept()
 {
     LOCKER(m_lock);
     if (m_pending.is_empty())
diff --git a/Kernel/Net/Socket.h b/Kernel/Net/Socket.h
index ff129f8e54..af9e257a37 100644
--- a/Kernel/Net/Socket.h
+++ b/Kernel/Net/Socket.h
@@ -25,7 +25,7 @@ class FileDescription;
 
 class Socket : public File {
 public:
-    static KResultOr<Retained<Socket>> create(int domain, int type, int protocol);
+    static KResultOr<NonnullRefPtr<Socket>> create(int domain, int type, int protocol);
     virtual ~Socket() override;
 
     int domain() const { return m_domain; }
@@ -33,7 +33,7 @@ public:
     int protocol() const { return m_protocol; }
 
     bool can_accept() const { return !m_pending.is_empty(); }
-    RetainPtr<Socket> accept();
+    RefPtr<Socket> accept();
     bool is_connected() const { return m_connected; }
     KResult listen(int backlog);
 
@@ -89,14 +89,14 @@ private:
     timeval m_receive_deadline { 0, 0 };
     timeval m_send_deadline { 0, 0 };
 
-    Vector<RetainPtr<Socket>> m_pending;
+    Vector<RefPtr<Socket>> m_pending;
 };
 
 class SocketHandle {
 public:
     SocketHandle() {}
 
-    SocketHandle(RetainPtr<Socket>&& socket)
+    SocketHandle(RefPtr<Socket>&& socket)
         : m_socket(move(socket))
     {
         if (m_socket)
@@ -126,5 +126,5 @@ public:
     const Socket& socket() const { return *m_socket; }
 
 private:
-    RetainPtr<Socket> m_socket;
+    RefPtr<Socket> m_socket;
 };
diff --git a/Kernel/Net/TCPSocket.cpp b/Kernel/Net/TCPSocket.cpp
index c38f3c3cd6..595958dd02 100644
--- a/Kernel/Net/TCPSocket.cpp
+++ b/Kernel/Net/TCPSocket.cpp
@@ -15,7 +15,7 @@ Lockable<HashMap<word, TCPSocket*>>& TCPSocket::sockets_by_port()
 
 TCPSocketHandle TCPSocket::from_port(word port)
 {
-    RetainPtr<TCPSocket> socket;
+    RefPtr<TCPSocket> socket;
     {
         LOCKER(sockets_by_port().lock());
         auto it = sockets_by_port().resource().find(port);
@@ -38,7 +38,7 @@ TCPSocket::~TCPSocket()
     sockets_by_port().resource().remove(local_port());
 }
 
-Retained<TCPSocket> TCPSocket::create(int protocol)
+NonnullRefPtr<TCPSocket> TCPSocket::create(int protocol)
 {
     return adopt(*new TCPSocket(protocol));
 }
diff --git a/Kernel/Net/TCPSocket.h b/Kernel/Net/TCPSocket.h
index a54d04417d..905089abba 100644
--- a/Kernel/Net/TCPSocket.h
+++ b/Kernel/Net/TCPSocket.h
@@ -4,7 +4,7 @@
 
 class TCPSocket final : public IPv4Socket {
 public:
-    static Retained<TCPSocket> create(int protocol);
+    static NonnullRefPtr<TCPSocket> create(int protocol);
     virtual ~TCPSocket() override;
 
     enum class State {
@@ -49,7 +49,7 @@ class TCPSocketHandle : public SocketHandle {
 public:
     TCPSocketHandle() {}
 
-    TCPSocketHandle(RetainPtr<TCPSocket>&& socket)
+    TCPSocketHandle(RefPtr<TCPSocket>&& socket)
         : SocketHandle(move(socket))
     {
     }
diff --git a/Kernel/Net/UDPSocket.cpp b/Kernel/Net/UDPSocket.cpp
index 6ae66cfb09..0d1b815d37 100644
--- a/Kernel/Net/UDPSocket.cpp
+++ b/Kernel/Net/UDPSocket.cpp
@@ -15,7 +15,7 @@ Lockable<HashMap<word, UDPSocket*>>& UDPSocket::sockets_by_port()
 
 UDPSocketHandle UDPSocket::from_port(word port)
 {
-    RetainPtr<UDPSocket> socket;
+    RefPtr<UDPSocket> socket;
     {
         LOCKER(sockets_by_port().lock());
         auto it = sockets_by_port().resource().find(port);
@@ -38,7 +38,7 @@ UDPSocket::~UDPSocket()
     sockets_by_port().resource().remove(local_port());
 }
 
-Retained<UDPSocket> UDPSocket::create(int protocol)
+NonnullRefPtr<UDPSocket> UDPSocket::create(int protocol)
 {
     return adopt(*new UDPSocket(protocol));
 }
diff --git a/Kernel/Net/UDPSocket.h b/Kernel/Net/UDPSocket.h
index 80ef09b7bf..3cd147d7e5 100644
--- a/Kernel/Net/UDPSocket.h
+++ b/Kernel/Net/UDPSocket.h
@@ -6,7 +6,7 @@ class UDPSocketHandle;
 
 class UDPSocket final : public IPv4Socket {
 public:
-    static Retained<UDPSocket> create(int protocol);
+    static NonnullRefPtr<UDPSocket> create(int protocol);
     virtual ~UDPSocket() override;
 
     static UDPSocketHandle from_port(word);
@@ -27,7 +27,7 @@ class UDPSocketHandle : public SocketHandle {
 public:
     UDPSocketHandle() {}
 
-    UDPSocketHandle(RetainPtr<UDPSocket>&& socket)
+    UDPSocketHandle(RefPtr<UDPSocket>&& socket)
         : SocketHandle(move(socket))
     {
     }
diff --git a/Kernel/Process.cpp b/Kernel/Process.cpp
index d671d177df..52ff29dcca 100644
--- a/Kernel/Process.cpp
+++ b/Kernel/Process.cpp
@@ -105,7 +105,7 @@ Region* Process::allocate_region(VirtualAddress vaddr, size_t size, const String
     return m_regions.last().ptr();
 }
 
-Region* Process::allocate_file_backed_region(VirtualAddress vaddr, size_t size, RetainPtr<Inode>&& inode, const String& name, int prot)
+Region* Process::allocate_file_backed_region(VirtualAddress vaddr, size_t size, RefPtr<Inode>&& inode, const String& name, int prot)
 {
     auto range = allocate_range(vaddr, size);
     if (!range.is_valid())
@@ -115,7 +115,7 @@ Region* Process::allocate_file_backed_region(VirtualAddress vaddr, size_t size,
     return m_regions.last().ptr();
 }
 
-Region* Process::allocate_region_with_vmo(VirtualAddress vaddr, size_t size, Retained<VMObject>&& vmo, size_t offset_in_vmo, const String& name, int prot)
+Region* Process::allocate_region_with_vmo(VirtualAddress vaddr, size_t size, NonnullRefPtr<VMObject>&& vmo, size_t offset_in_vmo, const String& name, int prot)
 {
     auto range = allocate_range(vaddr, size);
     if (!range.is_valid())
@@ -334,7 +334,7 @@ int Process::do_exec(String path, Vector<String> arguments, Vector<String> envir
 
     auto vmo = VMObject::create_file_backed(description->inode());
     vmo->set_name(description->absolute_path());
-    RetainPtr<Region> region = allocate_region_with_vmo(VirtualAddress(), metadata.size, vmo.copy_ref(), 0, vmo->name(), PROT_READ);
+    RefPtr<Region> region = allocate_region_with_vmo(VirtualAddress(), metadata.size, vmo.copy_ref(), 0, vmo->name(), PROT_READ);
     ASSERT(region);
 
     if (this != &current->process()) {
@@ -516,7 +516,7 @@ Process* Process::create_user_process(const String& path, uid_t uid, gid_t gid,
     if (arguments.is_empty()) {
         arguments.append(parts.last());
     }
-    RetainPtr<Custody> cwd;
+    RefPtr<Custody> cwd;
     {
         InterruptDisabler disabler;
         if (auto* parent = Process::from_pid(parent_pid))
@@ -562,7 +562,7 @@ Process* Process::create_kernel_process(String&& name, void (*e)())
     return process;
 }
 
-Process::Process(String&& name, uid_t uid, gid_t gid, pid_t ppid, RingLevel ring, RetainPtr<Custody>&& cwd, RetainPtr<Custody>&& executable, TTY* tty, Process* fork_parent)
+Process::Process(String&& name, uid_t uid, gid_t gid, pid_t ppid, RingLevel ring, RefPtr<Custody>&& cwd, RefPtr<Custody>&& executable, TTY* tty, Process* fork_parent)
     : m_name(move(name))
     , m_pid(next_pid++) // FIXME: RACE: This variable looks racy!
     , m_uid(uid)
@@ -2445,7 +2445,7 @@ struct SharedBuffer {
     Region* m_pid2_region { nullptr };
     bool m_pid1_writable { false };
     bool m_pid2_writable { false };
-    Retained<VMObject> m_vmo;
+    NonnullRefPtr<VMObject> m_vmo;
 };
 
 static int s_next_shared_buffer_id;
@@ -2734,7 +2734,7 @@ void Process::FileDescriptionAndFlags::clear()
     flags = 0;
 }
 
-void Process::FileDescriptionAndFlags::set(Retained<FileDescription>&& d, dword f)
+void Process::FileDescriptionAndFlags::set(NonnullRefPtr<FileDescription>&& d, dword f)
 {
     description = move(d);
     flags = f;
diff --git a/Kernel/Process.h b/Kernel/Process.h
index 46f5b895a1..c8c7583603 100644
--- a/Kernel/Process.h
+++ b/Kernel/Process.h
@@ -211,7 +211,7 @@ public:
     void set_tty(TTY* tty) { m_tty = tty; }
 
     size_t region_count() const { return m_regions.size(); }
-    const Vector<Retained<Region>>& regions() const { return m_regions; }
+    const Vector<NonnullRefPtr<Region>>& regions() const { return m_regions; }
     void dump_regions();
 
     ProcessTracer* tracer() { return m_tracer.ptr(); }
@@ -248,8 +248,8 @@ public:
 
     bool is_superuser() const { return m_euid == 0; }
 
-    Region* allocate_region_with_vmo(VirtualAddress, size_t, Retained<VMObject>&&, size_t offset_in_vmo, const String& name, int prot);
-    Region* allocate_file_backed_region(VirtualAddress, size_t, RetainPtr<Inode>&&, const String& name, int prot);
+    Region* allocate_region_with_vmo(VirtualAddress, size_t, NonnullRefPtr<VMObject>&&, size_t offset_in_vmo, const String& name, int prot);
+    Region* allocate_file_backed_region(VirtualAddress, size_t, RefPtr<Inode>&&, const String& name, int prot);
     Region* allocate_region(VirtualAddress, size_t, const String& name, int prot = PROT_READ | PROT_WRITE, bool commit = true);
     bool deallocate_region(Region& region);
 
@@ -273,7 +273,7 @@ private:
     friend class Scheduler;
     friend class Region;
 
-    Process(String&& name, uid_t, gid_t, pid_t ppid, RingLevel, RetainPtr<Custody>&& cwd = nullptr, RetainPtr<Custody>&& executable = nullptr, TTY* = nullptr, Process* fork_parent = nullptr);
+    Process(String&& name, uid_t, gid_t, pid_t ppid, RingLevel, RefPtr<Custody>&& cwd = nullptr, RefPtr<Custody>&& executable = nullptr, TTY* = nullptr, Process* fork_parent = nullptr);
 
     Range allocate_range(VirtualAddress, size_t);
 
@@ -287,7 +287,7 @@ private:
 
     Thread* m_main_thread { nullptr };
 
-    RetainPtr<PageDirectory> m_page_directory;
+    RefPtr<PageDirectory> m_page_directory;
 
     Process* m_prev { nullptr };
     Process* m_next { nullptr };
@@ -307,8 +307,8 @@ private:
     struct FileDescriptionAndFlags {
         operator bool() const { return !!description; }
         void clear();
-        void set(Retained<FileDescription>&& d, dword f = 0);
-        RetainPtr<FileDescription> description;
+        void set(NonnullRefPtr<FileDescription>&& d, dword f = 0);
+        RefPtr<FileDescription> description;
         dword flags { 0 };
     };
     Vector<FileDescriptionAndFlags> m_fds;
@@ -319,14 +319,14 @@ private:
     byte m_termination_status { 0 };
     byte m_termination_signal { 0 };
 
-    RetainPtr<Custody> m_executable;
-    RetainPtr<Custody> m_cwd;
+    RefPtr<Custody> m_executable;
+    RefPtr<Custody> m_cwd;
 
     TTY* m_tty { nullptr };
 
     Region* region_from_range(VirtualAddress, size_t);
 
-    Vector<Retained<Region>> m_regions;
+    Vector<NonnullRefPtr<Region>> m_regions;
 
     VirtualAddress m_return_to_ring3_from_signal_trampoline;
     VirtualAddress m_return_to_ring0_from_signal_trampoline;
@@ -345,7 +345,7 @@ private:
 
     unsigned m_syscall_count { 0 };
 
-    RetainPtr<ProcessTracer> m_tracer;
+    RefPtr<ProcessTracer> m_tracer;
     OwnPtr<ELFLoader> m_elf_loader;
 
     Lock m_big_lock { "Process" };
diff --git a/Kernel/ProcessTracer.h b/Kernel/ProcessTracer.h
index 0b71b0ba0a..8733c0a813 100644
--- a/Kernel/ProcessTracer.h
+++ b/Kernel/ProcessTracer.h
@@ -6,7 +6,7 @@
 
 class ProcessTracer : public File {
 public:
-    static Retained<ProcessTracer> create(pid_t pid) { return adopt(*new ProcessTracer(pid)); }
+    static NonnullRefPtr<ProcessTracer> create(pid_t pid) { return adopt(*new ProcessTracer(pid)); }
     virtual ~ProcessTracer() override;
 
     bool is_dead() const { return m_dead; }
diff --git a/Kernel/SharedMemory.cpp b/Kernel/SharedMemory.cpp
index 6100aee70c..fec48ce082 100644
--- a/Kernel/SharedMemory.cpp
+++ b/Kernel/SharedMemory.cpp
@@ -4,15 +4,15 @@
 #include <Kernel/SharedMemory.h>
 #include <Kernel/VM/VMObject.h>
 
-Lockable<HashMap<String, RetainPtr<SharedMemory>>>& shared_memories()
+Lockable<HashMap<String, RefPtr<SharedMemory>>>& shared_memories()
 {
-    static Lockable<HashMap<String, RetainPtr<SharedMemory>>>* map;
+    static Lockable<HashMap<String, RefPtr<SharedMemory>>>* map;
     if (!map)
-        map = new Lockable<HashMap<String, RetainPtr<SharedMemory>>>;
+        map = new Lockable<HashMap<String, RefPtr<SharedMemory>>>;
     return *map;
 }
 
-KResultOr<Retained<SharedMemory>> SharedMemory::open(const String& name, int flags, mode_t mode)
+KResultOr<NonnullRefPtr<SharedMemory>> SharedMemory::open(const String& name, int flags, mode_t mode)
 {
     UNUSED_PARAM(flags);
     LOCKER(shared_memories().lock());
diff --git a/Kernel/SharedMemory.h b/Kernel/SharedMemory.h
index f7ec96f495..7ab7d7497a 100644
--- a/Kernel/SharedMemory.h
+++ b/Kernel/SharedMemory.h
@@ -11,7 +11,7 @@ class VMObject;
 
 class SharedMemory : public File {
 public:
-    static KResultOr<Retained<SharedMemory>> open(const String& name, int flags, mode_t);
+    static KResultOr<NonnullRefPtr<SharedMemory>> open(const String& name, int flags, mode_t);
     static KResult unlink(const String& name);
     virtual ~SharedMemory() override;
 
@@ -39,5 +39,5 @@ private:
     uid_t m_uid { 0 };
     gid_t m_gid { 0 };
     mode_t m_mode { 0 };
-    RetainPtr<VMObject> m_vmo;
+    RefPtr<VMObject> m_vmo;
 };
diff --git a/Kernel/TTY/MasterPTY.h b/Kernel/TTY/MasterPTY.h
index accb6902bc..d4965cd76a 100644
--- a/Kernel/TTY/MasterPTY.h
+++ b/Kernel/TTY/MasterPTY.h
@@ -29,7 +29,7 @@ private:
     virtual int ioctl(FileDescription&, unsigned request, unsigned arg) override;
     virtual const char* class_name() const override { return "MasterPTY"; }
 
-    RetainPtr<SlavePTY> m_slave;
+    RefPtr<SlavePTY> m_slave;
     unsigned m_index;
     bool m_closed { false };
     DoubleBuffer m_buffer;
diff --git a/Kernel/TTY/PTYMultiplexer.cpp b/Kernel/TTY/PTYMultiplexer.cpp
index 3b8b596502..6a9b645e0c 100644
--- a/Kernel/TTY/PTYMultiplexer.cpp
+++ b/Kernel/TTY/PTYMultiplexer.cpp
@@ -28,7 +28,7 @@ PTYMultiplexer::~PTYMultiplexer()
 {
 }
 
-KResultOr<Retained<FileDescription>> PTYMultiplexer::open(int options)
+KResultOr<NonnullRefPtr<FileDescription>> PTYMultiplexer::open(int options)
 {
     UNUSED_PARAM(options);
     LOCKER(m_lock);
diff --git a/Kernel/TTY/PTYMultiplexer.h b/Kernel/TTY/PTYMultiplexer.h
index b25a5674fc..5a5e8f51b5 100644
--- a/Kernel/TTY/PTYMultiplexer.h
+++ b/Kernel/TTY/PTYMultiplexer.h
@@ -15,7 +15,7 @@ public:
     static PTYMultiplexer& the();
 
     // ^CharacterDevice
-    virtual KResultOr<Retained<FileDescription>> open(int options) override;
+    virtual KResultOr<NonnullRefPtr<FileDescription>> open(int options) override;
     virtual ssize_t read(FileDescription&, byte*, ssize_t) override { return 0; }
     virtual ssize_t write(FileDescription&, const byte*, ssize_t) override { return 0; }
     virtual bool can_read(FileDescription&) const override { return true; }
diff --git a/Kernel/TTY/SlavePTY.h b/Kernel/TTY/SlavePTY.h
index 83387d8731..71c79371fc 100644
--- a/Kernel/TTY/SlavePTY.h
+++ b/Kernel/TTY/SlavePTY.h
@@ -30,7 +30,7 @@ private:
     friend class MasterPTY;
     SlavePTY(MasterPTY&, unsigned index);
 
-    RetainPtr<MasterPTY> m_master;
+    RefPtr<MasterPTY> m_master;
     unsigned m_index;
     InodeIdentifier m_devpts_inode_id;
     String m_tty_name;
diff --git a/Kernel/Thread.h b/Kernel/Thread.h
index 91cd852e5e..bc00eb630f 100644
--- a/Kernel/Thread.h
+++ b/Kernel/Thread.h
@@ -176,10 +176,10 @@ private:
     dword m_pending_signals { 0 };
     dword m_signal_mask { 0 };
     dword m_kernel_stack_base { 0 };
-    RetainPtr<Region> m_kernel_stack_region;
-    RetainPtr<Region> m_kernel_stack_for_signal_handler_region;
+    RefPtr<Region> m_kernel_stack_region;
+    RefPtr<Region> m_kernel_stack_for_signal_handler_region;
     pid_t m_waitee_pid { -1 };
-    RetainPtr<FileDescription> m_blocked_description;
+    RefPtr<FileDescription> m_blocked_description;
     timeval m_select_timeout;
     SignalActionData m_signal_action_data[32];
     Region* m_signal_stack_user_region { nullptr };
diff --git a/Kernel/VM/MemoryManager.cpp b/Kernel/VM/MemoryManager.cpp
index bcc97d1b35..dd0f0f9ef0 100644
--- a/Kernel/VM/MemoryManager.cpp
+++ b/Kernel/VM/MemoryManager.cpp
@@ -81,7 +81,7 @@ void MemoryManager::initialize_paging()
 #endif
     m_quickmap_addr = VirtualAddress((1 * MB) - PAGE_SIZE);
 
-    RetainPtr<PhysicalRegion> region = nullptr;
+    RefPtr<PhysicalRegion> region = nullptr;
     bool region_is_super = false;
 
     for (auto* mmap = (multiboot_memory_map_t*)multiboot_info_ptr->mmap_addr; (unsigned long)mmap < multiboot_info_ptr->mmap_addr + multiboot_info_ptr->mmap_length; mmap = (multiboot_memory_map_t*)((unsigned long)mmap + mmap->size + sizeof(mmap->size))) {
@@ -151,7 +151,7 @@ void MemoryManager::initialize_paging()
 #endif
 }
 
-RetainPtr<PhysicalPage> MemoryManager::allocate_page_table(PageDirectory& page_directory, unsigned index)
+RefPtr<PhysicalPage> MemoryManager::allocate_page_table(PageDirectory& page_directory, unsigned index)
 {
     ASSERT(!page_directory.m_physical_pages.contains(index));
     auto physical_page = allocate_supervisor_physical_page();
@@ -444,7 +444,7 @@ PageFaultResponse MemoryManager::handle_page_fault(const PageFault& fault)
     return PageFaultResponse::ShouldCrash;
 }
 
-RetainPtr<Region> MemoryManager::allocate_kernel_region(size_t size, String&& name)
+RefPtr<Region> MemoryManager::allocate_kernel_region(size_t size, String&& name)
 {
     InterruptDisabler disabler;
 
@@ -478,11 +478,11 @@ void MemoryManager::deallocate_user_physical_page(PhysicalPage&& page)
     ASSERT_NOT_REACHED();
 }
 
-RetainPtr<PhysicalPage> MemoryManager::allocate_user_physical_page(ShouldZeroFill should_zero_fill)
+RefPtr<PhysicalPage> MemoryManager::allocate_user_physical_page(ShouldZeroFill should_zero_fill)
 {
     InterruptDisabler disabler;
 
-    RetainPtr<PhysicalPage> page = nullptr;
+    RefPtr<PhysicalPage> page = nullptr;
 
     for (auto& region : m_user_physical_regions) {
         page = region->take_free_page(false);
@@ -535,11 +535,11 @@ void MemoryManager::deallocate_supervisor_physical_page(PhysicalPage&& page)
     ASSERT_NOT_REACHED();
 }
 
-RetainPtr<PhysicalPage> MemoryManager::allocate_supervisor_physical_page()
+RefPtr<PhysicalPage> MemoryManager::allocate_supervisor_physical_page()
 {
     InterruptDisabler disabler;
 
-    RetainPtr<PhysicalPage> page = nullptr;
+    RefPtr<PhysicalPage> page = nullptr;
 
     for (auto& region : m_super_physical_regions) {
         page = region->take_free_page(true);
diff --git a/Kernel/VM/MemoryManager.h b/Kernel/VM/MemoryManager.h
index efa291e41c..605f35dd95 100644
--- a/Kernel/VM/MemoryManager.h
+++ b/Kernel/VM/MemoryManager.h
@@ -61,8 +61,8 @@ public:
         Yes
     };
 
-    RetainPtr<PhysicalPage> allocate_user_physical_page(ShouldZeroFill);
-    RetainPtr<PhysicalPage> allocate_supervisor_physical_page();
+    RefPtr<PhysicalPage> allocate_user_physical_page(ShouldZeroFill);
+    RefPtr<PhysicalPage> allocate_supervisor_physical_page();
     void deallocate_user_physical_page(PhysicalPage&&);
     void deallocate_supervisor_physical_page(PhysicalPage&&);
 
@@ -70,7 +70,7 @@ public:
 
     void map_for_kernel(VirtualAddress, PhysicalAddress);
 
-    RetainPtr<Region> allocate_kernel_region(size_t, String&& name);
+    RefPtr<Region> allocate_kernel_region(size_t, String&& name);
     void map_region_at_address(PageDirectory&, Region&, VirtualAddress, bool user_accessible);
 
     unsigned user_physical_pages() const { return m_user_physical_pages; }
@@ -93,7 +93,7 @@ private:
     void flush_entire_tlb();
     void flush_tlb(VirtualAddress);
 
-    RetainPtr<PhysicalPage> allocate_page_table(PageDirectory&, unsigned index);
+    RefPtr<PhysicalPage> allocate_page_table(PageDirectory&, unsigned index);
 
     void map_protected(VirtualAddress, size_t length);
 
@@ -214,7 +214,7 @@ private:
 
     PageTableEntry ensure_pte(PageDirectory&, VirtualAddress);
 
-    RetainPtr<PageDirectory> m_kernel_page_directory;
+    RefPtr<PageDirectory> m_kernel_page_directory;
     dword* m_page_table_zero { nullptr };
     dword* m_page_table_one { nullptr };
 
@@ -225,8 +225,8 @@ private:
     unsigned m_super_physical_pages { 0 };
     unsigned m_super_physical_pages_used { 0 };
 
-    Vector<Retained<PhysicalRegion>> m_user_physical_regions {};
-    Vector<Retained<PhysicalRegion>> m_super_physical_regions {};
+    Vector<NonnullRefPtr<PhysicalRegion>> m_user_physical_regions {};
+    Vector<NonnullRefPtr<PhysicalRegion>> m_super_physical_regions {};
 
     HashTable<VMObject*> m_vmos;
     HashTable<Region*> m_user_regions;
diff --git a/Kernel/VM/PageDirectory.h b/Kernel/VM/PageDirectory.h
index cf0876e438..fcf8ea83dc 100644
--- a/Kernel/VM/PageDirectory.h
+++ b/Kernel/VM/PageDirectory.h
@@ -10,8 +10,8 @@ class PageDirectory : public RefCounted<PageDirectory> {
     friend class MemoryManager;
 
 public:
-    static Retained<PageDirectory> create_for_userspace(const RangeAllocator* parent_range_allocator = nullptr) { return adopt(*new PageDirectory(parent_range_allocator)); }
-    static Retained<PageDirectory> create_at_fixed_address(PhysicalAddress paddr) { return adopt(*new PageDirectory(paddr)); }
+    static NonnullRefPtr<PageDirectory> create_for_userspace(const RangeAllocator* parent_range_allocator = nullptr) { return adopt(*new PageDirectory(parent_range_allocator)); }
+    static NonnullRefPtr<PageDirectory> create_at_fixed_address(PhysicalAddress paddr) { return adopt(*new PageDirectory(paddr)); }
     ~PageDirectory();
 
     dword cr3() const { return m_directory_page->paddr().get(); }
@@ -26,6 +26,6 @@ private:
     explicit PageDirectory(PhysicalAddress);
 
     RangeAllocator m_range_allocator;
-    RetainPtr<PhysicalPage> m_directory_page;
-    HashMap<unsigned, RetainPtr<PhysicalPage>> m_physical_pages;
+    RefPtr<PhysicalPage> m_directory_page;
+    HashMap<unsigned, RefPtr<PhysicalPage>> m_physical_pages;
 };
diff --git a/Kernel/VM/PhysicalPage.cpp b/Kernel/VM/PhysicalPage.cpp
index adc64e870b..49436a22af 100644
--- a/Kernel/VM/PhysicalPage.cpp
+++ b/Kernel/VM/PhysicalPage.cpp
@@ -2,7 +2,7 @@
 #include <Kernel/VM/PhysicalPage.h>
 #include <Kernel/kmalloc.h>
 
-Retained<PhysicalPage> PhysicalPage::create(PhysicalAddress paddr, bool supervisor, bool may_return_to_freelist)
+NonnullRefPtr<PhysicalPage> PhysicalPage::create(PhysicalAddress paddr, bool supervisor, bool may_return_to_freelist)
 {
     void* slot = kmalloc(sizeof(PhysicalPage));
     new (slot) PhysicalPage(paddr, supervisor, may_return_to_freelist);
diff --git a/Kernel/VM/PhysicalPage.h b/Kernel/VM/PhysicalPage.h
index e4422d14a0..a36200f266 100644
--- a/Kernel/VM/PhysicalPage.h
+++ b/Kernel/VM/PhysicalPage.h
@@ -28,7 +28,7 @@ public:
         }
     }
 
-    static Retained<PhysicalPage> create(PhysicalAddress, bool supervisor, bool may_return_to_freelist = true);
+    static NonnullRefPtr<PhysicalPage> create(PhysicalAddress, bool supervisor, bool may_return_to_freelist = true);
 
     word ref_count() const { return m_retain_count; }
 
diff --git a/Kernel/VM/PhysicalRegion.cpp b/Kernel/VM/PhysicalRegion.cpp
index fd7021d977..436f17d144 100644
--- a/Kernel/VM/PhysicalRegion.cpp
+++ b/Kernel/VM/PhysicalRegion.cpp
@@ -6,7 +6,7 @@
 #include <Kernel/VM/PhysicalPage.h>
 #include <Kernel/VM/PhysicalRegion.h>
 
-Retained<PhysicalRegion> PhysicalRegion::create(PhysicalAddress lower, PhysicalAddress upper)
+NonnullRefPtr<PhysicalRegion> PhysicalRegion::create(PhysicalAddress lower, PhysicalAddress upper)
 {
     return adopt(*new PhysicalRegion(lower, upper));
 }
@@ -36,7 +36,7 @@ unsigned PhysicalRegion::finalize_capacity()
     return size();
 }
 
-RetainPtr<PhysicalPage> PhysicalRegion::take_free_page(bool supervisor)
+RefPtr<PhysicalPage> PhysicalRegion::take_free_page(bool supervisor)
 {
     ASSERT(m_pages);
 
diff --git a/Kernel/VM/PhysicalRegion.h b/Kernel/VM/PhysicalRegion.h
index 7cecc4b365..425a5900a7 100644
--- a/Kernel/VM/PhysicalRegion.h
+++ b/Kernel/VM/PhysicalRegion.h
@@ -10,7 +10,7 @@ class PhysicalRegion : public RefCounted<PhysicalRegion> {
     AK_MAKE_ETERNAL
 
 public:
-    static Retained<PhysicalRegion> create(PhysicalAddress lower, PhysicalAddress upper);
+    static NonnullRefPtr<PhysicalRegion> create(PhysicalAddress lower, PhysicalAddress upper);
     ~PhysicalRegion() {}
 
     void expand(PhysicalAddress lower, PhysicalAddress upper);
@@ -23,7 +23,7 @@ public:
     unsigned free() const { return m_pages - m_used; }
     bool contains(PhysicalPage& page) const { return page.paddr() >= m_lower && page.paddr() <= m_upper; }
 
-    RetainPtr<PhysicalPage> take_free_page(bool supervisor);
+    RefPtr<PhysicalPage> take_free_page(bool supervisor);
     void return_page_at(PhysicalAddress addr);
     void return_page(PhysicalPage&& page) { return_page_at(page.paddr()); }
 
diff --git a/Kernel/VM/Region.cpp b/Kernel/VM/Region.cpp
index 234fc4710b..e191ce2e25 100644
--- a/Kernel/VM/Region.cpp
+++ b/Kernel/VM/Region.cpp
@@ -15,7 +15,7 @@ Region::Region(const Range& range, const String& name, byte access, bool cow)
     MM.register_region(*this);
 }
 
-Region::Region(const Range& range, RetainPtr<Inode>&& inode, const String& name, byte access)
+Region::Region(const Range& range, RefPtr<Inode>&& inode, const String& name, byte access)
     : m_range(range)
     , m_vmo(VMObject::create_file_backed(move(inode)))
     , m_name(name)
@@ -25,7 +25,7 @@ Region::Region(const Range& range, RetainPtr<Inode>&& inode, const String& name,
     MM.register_region(*this);
 }
 
-Region::Region(const Range& range, Retained<VMObject>&& vmo, size_t offset_in_vmo, const String& name, byte access, bool cow)
+Region::Region(const Range& range, NonnullRefPtr<VMObject>&& vmo, size_t offset_in_vmo, const String& name, byte access, bool cow)
     : m_range(range)
     , m_offset_in_vmo(offset_in_vmo)
     , m_vmo(move(vmo))
@@ -66,7 +66,7 @@ bool Region::page_in()
     return true;
 }
 
-Retained<Region> Region::clone()
+NonnullRefPtr<Region> Region::clone()
 {
     ASSERT(current);
     if (m_shared || (is_readable() && !is_writable())) {
diff --git a/Kernel/VM/Region.h b/Kernel/VM/Region.h
index 1e0d374b17..9079280d2f 100644
--- a/Kernel/VM/Region.h
+++ b/Kernel/VM/Region.h
@@ -19,8 +19,8 @@ public:
     };
 
     Region(const Range&, const String&, byte access, bool cow = false);
-    Region(const Range&, Retained<VMObject>&&, size_t offset_in_vmo, const String&, byte access, bool cow = false);
-    Region(const Range&, RetainPtr<Inode>&&, const String&, byte access);
+    Region(const Range&, NonnullRefPtr<VMObject>&&, size_t offset_in_vmo, const String&, byte access, bool cow = false);
+    Region(const Range&, RefPtr<Inode>&&, const String&, byte access);
     ~Region();
 
     VirtualAddress vaddr() const { return m_range.base(); }
@@ -38,7 +38,7 @@ public:
     bool is_shared() const { return m_shared; }
     void set_shared(bool shared) { m_shared = shared; }
 
-    Retained<Region> clone();
+    NonnullRefPtr<Region> clone();
 
     bool contains(VirtualAddress vaddr) const
     {
@@ -97,10 +97,10 @@ public:
     }
 
 private:
-    RetainPtr<PageDirectory> m_page_directory;
+    RefPtr<PageDirectory> m_page_directory;
     Range m_range;
     size_t m_offset_in_vmo { 0 };
-    Retained<VMObject> m_vmo;
+    NonnullRefPtr<VMObject> m_vmo;
     String m_name;
     byte m_access { 0 };
     bool m_shared { false };
diff --git a/Kernel/VM/VMObject.cpp b/Kernel/VM/VMObject.cpp
index 34a8a2cf55..9bcd6875eb 100644
--- a/Kernel/VM/VMObject.cpp
+++ b/Kernel/VM/VMObject.cpp
@@ -3,7 +3,7 @@
 #include <Kernel/VM/MemoryManager.h>
 #include <Kernel/VM/VMObject.h>
 
-Retained<VMObject> VMObject::create_file_backed(RetainPtr<Inode>&& inode)
+NonnullRefPtr<VMObject> VMObject::create_file_backed(RefPtr<Inode>&& inode)
 {
     InterruptDisabler disabler;
     if (inode->vmo())
@@ -13,13 +13,13 @@ Retained<VMObject> VMObject::create_file_backed(RetainPtr<Inode>&& inode)
     return vmo;
 }
 
-Retained<VMObject> VMObject::create_anonymous(size_t size)
+NonnullRefPtr<VMObject> VMObject::create_anonymous(size_t size)
 {
     size = ceil_div(size, PAGE_SIZE) * PAGE_SIZE;
     return adopt(*new VMObject(size));
 }
 
-Retained<VMObject> VMObject::create_for_physical_range(PhysicalAddress paddr, size_t size)
+NonnullRefPtr<VMObject> VMObject::create_for_physical_range(PhysicalAddress paddr, size_t size)
 {
     size = ceil_div(size, PAGE_SIZE) * PAGE_SIZE;
     auto vmo = adopt(*new VMObject(paddr, size));
@@ -27,7 +27,7 @@ Retained<VMObject> VMObject::create_for_physical_range(PhysicalAddress paddr, si
     return vmo;
 }
 
-Retained<VMObject> VMObject::clone()
+NonnullRefPtr<VMObject> VMObject::clone()
 {
     return adopt(*new VMObject(*this));
 }
@@ -59,7 +59,7 @@ VMObject::VMObject(PhysicalAddress paddr, size_t size)
     ASSERT(m_physical_pages.size() == page_count());
 }
 
-VMObject::VMObject(RetainPtr<Inode>&& inode)
+VMObject::VMObject(RefPtr<Inode>&& inode)
     : m_inode(move(inode))
 {
     ASSERT(m_inode);
diff --git a/Kernel/VM/VMObject.h b/Kernel/VM/VMObject.h
index 5713d54395..ca6403f58e 100644
--- a/Kernel/VM/VMObject.h
+++ b/Kernel/VM/VMObject.h
@@ -18,10 +18,10 @@ class VMObject : public RefCounted<VMObject>
     friend class MemoryManager;
 
 public:
-    static Retained<VMObject> create_file_backed(RetainPtr<Inode>&&);
-    static Retained<VMObject> create_anonymous(size_t);
-    static Retained<VMObject> create_for_physical_range(PhysicalAddress, size_t);
-    Retained<VMObject> clone();
+    static NonnullRefPtr<VMObject> create_file_backed(RefPtr<Inode>&&);
+    static NonnullRefPtr<VMObject> create_anonymous(size_t);
+    static NonnullRefPtr<VMObject> create_for_physical_range(PhysicalAddress, size_t);
+    NonnullRefPtr<VMObject> clone();
 
     ~VMObject();
     bool is_anonymous() const { return !m_inode; }
@@ -34,8 +34,8 @@ public:
     void set_name(const String& name) { m_name = name; }
 
     size_t page_count() const { return m_size / PAGE_SIZE; }
-    const Vector<RetainPtr<PhysicalPage>>& physical_pages() const { return m_physical_pages; }
-    Vector<RetainPtr<PhysicalPage>>& physical_pages() { return m_physical_pages; }
+    const Vector<RefPtr<PhysicalPage>>& physical_pages() const { return m_physical_pages; }
+    Vector<RefPtr<PhysicalPage>>& physical_pages() { return m_physical_pages; }
 
     void inode_contents_changed(Badge<Inode>, off_t, ssize_t, const byte*);
     void inode_size_changed(Badge<Inode>, size_t old_size, size_t new_size);
@@ -43,7 +43,7 @@ public:
     size_t size() const { return m_size; }
 
 private:
-    VMObject(RetainPtr<Inode>&&);
+    VMObject(RefPtr<Inode>&&);
     explicit VMObject(VMObject&);
     explicit VMObject(size_t);
     VMObject(PhysicalAddress, size_t);
@@ -55,7 +55,7 @@ private:
     bool m_allow_cpu_caching { true };
     off_t m_inode_offset { 0 };
     size_t m_size { 0 };
-    RetainPtr<Inode> m_inode;
-    Vector<RetainPtr<PhysicalPage>> m_physical_pages;
+    RefPtr<Inode> m_inode;
+    Vector<RefPtr<PhysicalPage>> m_physical_pages;
     Lock m_paging_lock { "VMObject" };
 };
diff --git a/Kernel/init.cpp b/Kernel/init.cpp
index cde76f94e2..d1b9e381f8 100644
--- a/Kernel/init.cpp
+++ b/Kernel/init.cpp
@@ -86,7 +86,7 @@ VFS* vfs;
 
     auto dev_hd0 = IDEDiskDevice::create();
 
-    Retained<DiskDevice> root_dev = dev_hd0.copy_ref();
+    NonnullRefPtr<DiskDevice> root_dev = dev_hd0.copy_ref();
 
     root = root.substring(strlen("/dev/hda"), root.length() - strlen("/dev/hda"));
 
@@ -199,7 +199,7 @@ extern "C" [[noreturn]] void init()
 
     auto e1000 = E1000NetworkAdapter::autodetect();
 
-    Retained<ProcFS> new_procfs = ProcFS::create();
+    NonnullRefPtr<ProcFS> new_procfs = ProcFS::create();
     new_procfs->initialize();
 
     auto devptsfs = DevPtsFS::create();